Adjustable hydraulic shear



Jan. 27, 1 70 c, L; MEWHQL T 3,491,643

ADJUSTABLE HYDRAULIC SHEAR Filed Feb. 5, 1968 3 Sheets-Sheet l 4 l A, g, win!" l l lllllllllmnm "min I I I I K Hum 59 6O 5 L a I I 53 5 I" so 49 30 as as 39 n I 5| 1 1-153;:- :1 3| Hm g a A W 3-, M l5, I 36 22 0 55 I 5 3- I 58 1 IHHH in I v 4 0 WWW a Q a J") a a 0 CHARLES L n n fifi tm BY a6, a 5%: U w g m e ATTORNEYS Jan. 27, 1970 'c. L. MEINHOLDT 3,491,543

ADJUSTABLE HYDRAULIC SHEAR Filed Feb. 5, 1968 3 Sheets-Sheet 2 I INVENTOR. CHARLES L. MEINHOLDT BY 1 Q $4M ,m

ATTORNEYS Jan. 27, 1970 c. L. MEINHCLDT ADJUSTABLE HYDRAULIC SHEAR 3 Sheets-Sheet 5 Filed Feb. 5, 1968 AIw INVENTOR. CHARLES L. MEINHOLDT WWJOL ATTO RNEYS United States Patent 3,491,643 ADJUSTABLE HYDRAULIC SHEAR Charles L. Meinholdt, 1928 N. Topeka Blvd., P.0. Box 8191, Topeka, Kans. 66608 Filed Feb. 5, 1968, Ser. No. 702,941 Int. Cl. B26d /12 US. Cl. 83625 Claims ABSTRACT OF THE DISCLOSURE Metal working apparatus, such as shears and press brakes, having a fixed member extending between spaced standards and a movable member extending between said standards and movable toward and away from the fixed member to engage a metal workpiece therebetween. The apparatus includes an elongate cross beam secured to the standards and spaced above the fixed member, a pair of arms pivotally mounted in longitudinal spaced relation on the cross beam at a first pivotal con necting point of each arm, an elongate longitudinally adjustable strut pivotally connected to a second pivotal connecting point of each arm, a pair of links pivotally connected to a third pivotal connecting point on respective arms and secured to the movable member, and extensible and retractable hydraulic means having one end pivotally mounted on the cross beam and the other end pivotally connected to one of the arms for moving the movable member toward and away from the fixed member. The adjustable strut is operable to level the movable member or to effect a desired tilt thereof.

a vertical stroke of the movable member toward and away from a fixed metal engaging member; to provide such a linkage which has a pair of spaced arms each pivotally connected to a cross beam in the metal working apparatus at a first pivotal connecting point on each arm, a longitudinally adjustable strut pivotally connected to each arm at a second pivotal connecting point, a pair of links connected to the movable member and each pivotally connected to a respective arm at a third pivotal connecting point; to provide positive control for the level adjustment of the movable member relative to the fixed member; to provide a tilted shearing blade on the movable member and a vertical shearing blade on the fixed member whereby square burr free cu-t edges are produced; and to provide such a linkage which is smooth, positive, and shock-free in operation.

Other objects and advantages of this invention will become apparent from the following description taken in connection with the accompanying drawings wherein are set forth by way of illustration and example certain embodiments of this invention.

FIG. 1 is a perspective view of a metal working apparatus embodying features of the present invention.

FIG. 2 is an elevational view of the metal working apparatus with portions broken away to show the adjustment linkage and mechanism for controlling the stroke of movable metal engaging member.

FIG. 3 is an elevational view showing the adjustment linkage in a metal engaging position.

ice

FIG. 4 is an elevational view of the adjustment linkage showing an adjusted length of a strut therein.

FIG. 5 is a sectional view of the metal working apparatus taken on line 55, FIG. 2 particularly showing the adjustment linkage and power mechanism.

FIG. 6 is a detailed sectional view taken on line 6-6, FIG. 2 showing the connection between the drive and the linkage.

FIG. 7 is an elevational view of a modified form of the adjustment linkage.

FIG. 8 is a sectional view through the modified linkage taken on line 88, FIG. 7 particularly showing modified metal working members and the modified adjustment linkage.

Referring more in detail to the drawings:

The reference numeral 1 generally designates a metal working apparatus, embodying the present invention and having a movable blade or member cooperating with a stationary member in forming or shearing metal or other material. Examples of such apparatus is a press brake or a shear. The apparatus 1 in the illustrated structure includes an elongate frame 2, preferably of welded construction, having a beam 3 and having spaced side standards 4 and 5 respectively extending upwardly therefrom. A fixed elongate lower ram bed 6 is suitably secured to the beam 3 and extends horizontally between the standards 4 and 5. A fixed metal engaging member 8 is suitably mounted on the ram bed 6 and also extends horizontally between the standards 4 and 5. An elongate horizontally extending cross beam 9 is composed of a forward bar 10 and a rear bar 11 mutually parallel and maintained in spaced relation by means of suitable spaced web members 12. The cross beam 9 is suitably secured, preferably by Welding, at opposite ends 13 and 14 thereof to the respective standards 4 and 5 at a position spaced above the beam 3 and above the fixed metal engaging member 8. An elongate movable upper ram 15 extends between the standards 4 and 5 and has a movable upper metal engaging member 16 suitably secured thereto by means of suitable spaced fastening devices, such as screws or bolts 17.

The apparatus 1 has suitable guides or ways for defining the path of the upper ram 15. In the illustrated structure suitable spaced structural members, such as pairs of angles 18 and 19, are suitably secured adjacent opposite ends of the cross beam 9, preferably by welding, for receiving opposite ends of the movable upper ram 15 therebetween. Each of the pairs of angles 18 and 19 have a plurality of suitable spaced adjusting members, such as shafts 20 extending therethrough for positioning spaced guide plates 21 and 22. In the illustrated structure, the shafts have one end threaded to be received in a threaded socket in the guide plates 21 and 22 and a head 23 on the other end to adjust the position of the guide plates. Suitable bars 24 are mounted on the angles 18 and 19 to resist horizontal forces on the guide plates 21 and 22. The guide plates 21 and 22 slidably contact opposite sides of the respective ends of the movable upper ram 15 for vertically guiding the upper metal engaging member 16 in cooperation with the fixed metal engaging member 8. Suitable covers (not shown) are mounted on the angles -18 and 19 to protect the guide plates 21 and 22 against dirt or accidental contact which may cause excessive wear or otherwise upset the adjustment thereof.

A power operated linkage 25 is operative to raise and lower the upper metal engaging member 16 to brake, bend or shear a metal workpiece 26 by pressing or cutting in cooperation with the fixed metal engaging member 8. In the illustrated structure a pair of bell cranks shown as generally triangular elongate arms 27 and 28 respectively each have three pivotal connecting points thereon designated 29, 30 and 31 respectively. The pivotal connecting points 29, 30 and 31 are in mutually spaced relation and form triangular patterns on the respective arms 27 and 28 which are pivotally mounted in laterally spaced and parallel relation at a first of the pivotal connecting points, as for example point 29, on the' cross beam 9 as best illustrated in FIGS. 2 and 3. The arms 27 and 28 preferably are mounted between the forward and rear bars and 11 of the cross beam 9 and are adapted for pivotal motion in a vertical plane parallel to the metal engaging members 8 and 16. An elongate horizontally extending strut 32 is pivotally mounted at opposite ends 33 and 34 thereof to a second of the pivotal connecting points, as for example point 30 on the respective arms 27 and 28 for maintaining said arms in a selected spaced relation while permitting pivoting on the cross beam 9 and operation of the member 16, as described hereinafter.

The upper metal engaging member 16 is actuated by the bell cranks by spaced elongate links 35 and 36 respectively each pivotally connected at their respective upper ends 37 to third pivotal connecting point 31 on the arms 27 and 28. The lower ends 38 of the links 35 and 36 are pivotally connected at spaced positions to the movable upper ram for vertically suspending the upper metal engaging member 16.

It is preferable that the links 35 and 36 be of identical length; that the three pivotal connecting points 29, and 31 form identical triangular patterns on each of the arms 27 and 28; and that the connection to the cross beam 9 at the first pivotal connecting points 29 be positioned to provide even down travel of the upper ram 15 unless the length of the strut 32 is adjusted, as later described. However, the links and 36 may be of different lengths for a preliminary inclination of the blade or movable ram if desired.

An actuating structure of an extensible type is connected to the cross beam or the bell cranks or connected parts to operate the blade or forming member. In the illustrated structure, a pair of extensible and retractable hydraulic rams 39 and 40 respectively are each pivotally mounted at one end 41 thereof to the cross beam 9 by a suitable fixed mounting platform 42. The other ends 43 of the rams 39 and 40 respectively are pivotally connected to the second connecting point 30 of one of the arms, as for example arm 27. The hydraulic rams 39 and 40, within their range of extension, remain at a suitable angle to the arms 27 and 28 for selectively pivoting same upon extension and retraction, as best shown in FIGS. 2 and 3.

The strut 32 is adjustable in length with a change in snch length operating to move the second pivotal connecting point 30 of the arm 27 toward or away from the point 30 of the arm 28 thereby levelling the upper ram 15 and member 16 for down travel uniformly over the entire bed length in press brakes. The adjustment of the strut length in shears and the like effect tilting of either end of the upper ram -15 and the upper metal engaging member 16 thereon to even the wear and extend the life thereof. In the illustrated structure, the connections of the strut 32 to the arms 27 and 28 prevent rotation about a longitudinal axis and the strut 32 consists of two sections 44 and 45 with adjacent ends 46 and 47 having ;crew threads thereon. The threads on the ends '46 and 17 are opposite, as for example, end 46 has right hand threads and end 47 has left hand threads. A suitable rigid connecting member, such as a sleeve 48, has a bore with ends internally threaded to receive the respective :hreaded ends 46 and 47 whereby rotation of the sleeve in one direction extends the strut 32 and rotation in the opposite direction contracts said strut. The sleeve 48 and ;ections 44 and 45 cooperate to form a rigid member with ;aid section longitudinally aligned.

It is preferable to effect the adjustment of the strut ength from a remote position and also by power, and in my desired amount. In the illustrated structure, suitable power means is operatively connected to the sleeve 48 for rotating same. The power means or drive may be of any suitable form such as a motor with a speed reducer connected to the sleeve. In the illustrated structure a reversible drive electric motor 49 having a gear reducer in the housing 50 thereof is mounted on a bnacket 51 which is iixed on a strut section, such as section 45. The output shaft 52 of the motor has a gear 53 thereon meshing with a gear 54 fixed on the sleeve 48. While gears are shown, other transmission structures such as belts or chains could be used. The motor 49 is connected in a suitable circuit with control switches 55 arranged for easy access to the operator as shown in FIG. l.

A suitabe hydraulic pump 56 is mounted above the linkage 25 and operatively communicates with the hydraulic rams 39 and 4%) through suitable tubing 57, in a conventional manner, whereby pressure can be applied for either extending or retracting the rams 39 and 40. Conventional control valves 58 are responsive to the position of suitable manual control mechanisms, such as a foot switch 59, said valves being in the connections to the rams 39 and 40, for hydraulically extending and retracting same at desired variable speeds. it is noted that the foot switch 59 communicates electrically with the control valves 58 through a suitable electric cable 60 whereby the metal working apparatus operator may control the apparatus from any standing position at either end of the front of the apparatus.

The hydraulic pump 56 is driven, in the illustrated example, by a suitable electric motor 64 powered through conventional electric cables 65 connected to a suitable source of electrical current (not shown). A control box 66 is mounted on the side standard 4 and is connected to the cables 65 thereby permitting the actuation of the electric motor 64 when operation of the metal working apparatus 1 is desired.

In the illustrated structure, the hydraulic pump 56, and the electric motor 64 are mounted on or positioned above an upper platform or shelf 67 positioned above and to one side of the cross beam 9. The complete hydraulic and mechanical actuation system including the linkage 25 is thereby entirely removed from the metal working area providing a safe, clear, and unrestricted area for the apparatus operator to maneuver the metal workpiece 26.

In operation, the positioning of the foot switch 59 rotates the arms 27 and 28 by the extension or retraction of the hydraulic rams 39 and 40 for raising or lowering the movable upper ram 15 to provide a pressing action between the metal engaging members 8 and 16. Stopping during stroke, reversal of the pressing action, and also control over the speed of pressing action is easily obtained by manipulating the foot switch 59. The guide plates 24 are easily adjustable to maintain the most eflicient cooperation between the metal engaging members 8 and 16 and, as noted above, the actuating of the control switches 55 will cause the motor to effect desired adjusting of the length of the strut 32 and thereby adjust the tilt or lead of either end of the movable metal engaging member 16 to even the wear and extend the life thereof particularly in a shear and to level the member 16 in a press brake.

The above described metal working apparatus is simple to operate, easy to control, reliable in use, and permits pressing unexpectedly heavy material without the usual jar or shock normally associated with such operation thereby eliminating the need for extensive foundations, or providing vibration dampening between the apparatus and the supporting structure (not shown).

FIGS. 7 and 8 illustrate a modified form of the metal working apparatus l which is in the form of a shear adapted for shearing or cutting the metal workpieces 26, such as sheet, plate or the like. A fixed elongate shearing blade 70 is secured to the frame bed 2 adjacent the rear edge 7 of the platform 3 by means of suitable spaced fastening devices, such as screws or bolts 71, and the blade extends horizontally between the standards 4 and 5. An elongate movable upper blade receiver 72 extends between the standards 4 and 5 and has an upper shearing blade 73 suitably secured thereto by means of suitable spaced fastening devices, such as bolts or screws 74. The blade 73 and receiver 72 are Supported and operated by links from arms 27 and 28. The arms 27 and 28 are connected by a strut and up and down movement of the blades is by rams 39 and 40 substantially in the same manner as the movable number 15 in the forms shown in FIGS. 1 to 4 inclusive.

As best illustrated in FIG. 7 the strut 75 consists of two sections 76 and 78 with one of the sections, as for example section 76, having one end 78 pivotally connected to the second pivotal connecting point 30 on the arm 27 and the other end 79 having a plurality of spaced transverse openings 80 therethrough. The other strut section 77 has one end 81 pivotally conected to the second pivotal connecting point 30 on the arm 28 and the other end 82 of the strut section 77 has at least one transverse opening 83 therethrough. A suitable strut connecting member, such as an elongate sleeve or plate 84, has openings 85 spaced from opposite ends thereof. Suitable fastening devices, such as bolts 87, secure the sleeve or plate 84 to the other ends 79 and 82 respectively. In the structure shown in FIG. 7 one bolt 87 extends through one of the openings in the plate or sleeve 84, as for example opening 85, and through the opening 83 in the other end 82 of the strut section 77. Another bolt 87 extends through the other opening 86 in the sleeve or plate 84 and through one of the selected openings 80 in the other end 79 of the strut section 76.

It is preferred that the links connecting the upper blade 73 be of different length and as shown the links 88 is longer than link 89 this results in longitudinally tilting of t the upper shearing blade 73 to thereby give a shearing action and adjustment of the strut length will vary the tilt and provide longer blade life since most of the wear on the blades is normally experienced in the vicinity of the leading engagement of the respective blades.

As best illustrated in FIG. 8, the upper blade receiver 72 and the upper shearing blade 73 is in a laterally tilted relation with the fixed shearing blade 70. In the illustrated structure, the fixed shearing blade 70 is vertical and the upper shearing blade 73 is laterally tilted from the vertical in the nature of approximately two degrees (2) so that a leading or cutting edge 90 of the upper shearing blade 73 moves toward a cutting edge 91 of the fixed shearing blade 70 and then away from the cutting edge 91 of the fixed shearing blade 70 and then away from the cutting edge 91 as the upper blade 73 travels downwardly. The tilt of the upper shearing blade is such that the cutting edge 90 first engages the cutting edge 91 and then a body portion 92 of the upper shearing blade 73 is engaged by the cutting edge 91 during downwardly travel of the upper shearing blade, The tilt of the upper shearing blade is surprisingly effective in producing burr-free square cut edges in thick or heavy metal workpieces.

An elongate hold-down member 93 extends horizontally between the side standards 4 and 5 adjacent the respective blades 70 and 73. The hold-down member 93 has suitable ribs 94 extending outwardly therefrom and presenting flat lower clamping surfaces 95 adapted to cooperate with the platform or surface 3 for clamping the work pieces 26 therebetween. Suitable guides 96 are secured to the side standards 4 and 5 and cooperate with opposite ends of the hold-down member 93 for maintaining a path of motion normal to the platform or surface 3.

A pair of vertically extending laterally spaced extensible and retractable hydraulic cylinders or rams 97 and 98 are each pivotally secured at their upper ends 99 to the Web members 12 of the cross beam 9 and at their lower ends 100 to the hold-down member 93 for selectively suspending and downwardly urging the hold-down member toward the platform or surface 3 of the frame bed 2. The hydraulic pump 55 also operatively communicates with the hyrdaulic cylinders 97 and 98 through suitable hose or tubing 101 in a conventional manner whereby pressure can be applied for either extending or retracting the respective hydraulic cylinders 97 and 98 and the hydraulic rams 39 and 40.

Suitable conventional control valves 102 are responsive to the position of suitable manual control mechanisms, such as an operators foot switch 103 which is suitably connected to the rams 39 and 40, as by an electric cable 104 which controls suitable remote controlled valves, such as solenoid valves (not shown), for operating the hydraulic pump 55 for hydraulically extending and retractmg at desired variable speeds the hydraulic cylinders or rams 39 and 40. Suitable controls, such as up and down push buttons 105 and 106 respectively, are operatively connected to the hydraulic cylinders 97 and 98 for hydraulically extending and retracting same.

In operation, activation of the down push button 106 causes the hold-down member 93 to produce clamping between the hold-down member and the platform or surface 3 for holding the sheet, plate or the like therebetween for shearing same. In response to the particular position of the foot switch 103 the arms 27 and 28 are rotated by the extension or retraction of the hydraulic rams 39 and 40 for raising or lowering the upper shearing blade 73 to provide a shearing action between the blades 70 and 73.

It is to be understood that while I have illustrated and described certain forms of this invention, it is not to be limited to these specific forms or arrangements of parts herein described and shown except insofar as such limitations are included in the claims.

What I claim and desire to secure by Letters Patent is:

1. A metal working apparatus comprising:

(a) a frame bed,

(b) a work member on said frame bed,

(c) An elongate cross beam spaced above said frame bed and fixed relative thereto,

(d) a movable member movable toward and away from said work member,

(e) a pair of arms each having a first and second and a third pivotal connecting point in mutually spaced relation thereon forming respective connecting point patterns on said arms, said arms being pivotally mounted in spaced relation at said respective first connectlng points on said cross beam,

(f) an elongate longitudinally adjustable strut pivotally connected to said second connecting points for maintaining said arms in controlled pivotal relation to each other during pivoting about said first connecting points on said cross beam,

(g) means operatively connecting said third connecting points to said movable member for vertical suspension of said movable member, and

(h) extensible means having one end mounted on said cross beam and the other end operatively connected relative to said arms and strut whereby extension and contraction of said extensible means selectively pivots said arms about said first connecting points for working metal placed between said work member and movable member by moving said movable member toward and away from said work member.

2. The metal working apparatus as set forth in claim 1 including:

(a) said extensible means being a pair of s aced parallel extensible and retractable hydraulic rams,

(b) said pair of rams having said other ends pivotally connected to one of said arms adjacent the second connecting point thereof, and

(c) said pair of rams extending at an angle to said arms thereby selectively pivoting same upon extension and retraction.

3. The metal working apparatus as set forth in claim 1 including:

(a) said strut having a first strut section having one end thereof connected to one of said arms and a second strut section having one end thereof connected to the other of said arms,

(b) rigid connecting means operatively connected to the other end of said first and said second strut sections, and

(c) means for moving said other ends toward and away from each other.

4. The metal working apparatus as set forth in claim 3 wherein:

(a) said first and second strut section other ends are threaded in opposite directions, and

(b) said connecting means is a sleeve having internally threaded ends for engaging said threaded other ends of said first and said second sections.

5. The metal working apparatus as set forth in claim 3 including:

(a) said rigid connecting means being an elongate strut connecting member having a plurality of spaced transverse openings through said strut connecting member,

(b) a plurality of spaced transverse openings in at least one of said first and said second strut sections and at least one transverse opening in the other first section, and

(c) fastening devices extending through said elongate strut connecting member and engaging one of said openings in each of said first and second strut sections whereby the spacing between said strut section other ends is adjustable longitudinally of said strut.

6. The metal working apparatus as set forth in claim 5 including:

(a) said work member having a shearing blade secured thereto,

(b) said movable member having a shearing blade secured thereto, and

(c) said shearing blade on said movable member being in a tilted relation with said shearing blade on said work member whereby material between said blades is cut with square burr free edges.

7. The metal working apparatus as set forth in claim 3 wherein:

(a) said other ends of said first and said second strut sections are threaded,

(b) said rigid connecting means has internally threaded portions to receive said threaded other ends, and

(0) power means operatively connected to said rigid connecting means for rotating said internally thread portions about said first and second sections of said strut and adjusting spacing between said second connecting points of said pair of arms.

8. The metal working apparatus as set forth in c im 7 including:

(a) a reversible drive motor having a drive shaft extending outwardly therefrom,

(-b) a first power transmitting member mounted on one end of said drive shaft, and

(c) a second power transmitting member mounted on said sleeve, whereby said drive motor is operative to move said other ends of said first and said second strut sections toward and away from each other.

9. The metal working apparatus as set forth in claim 8 wherein:

(a) said first power transmitting member is a first sprocket wheel,

(-b) said second power transmitting member is a second sprocket wheel, and

(c) an endless flexible connecting chain engages said first and second sprocket wheels for moving said first and said strut sections toward and away from each other.

10. The metal working apparatus as set forth in claim 8 including:

(a) said drive motor being fixedly mounted on one of said strut sections and movable therewith, and

(b) said arms and said strut sections and said extensible means being above said movable member whereby metal working area is obstruction free.

References Cited UNITED STATES PATENTS 1,003,497 9/ 1911 Optenberg. 3,054,317 9/1962 Castle 83-640 X 3,140,654 7/1964 Jewett 272 X 3,157,084 11/1964 Memboldt 83-636 X FOREIGN PATENTS 255,780 7/ 1926 Great Britain.

FRANK T. YOST, Primary Examiner US. Cl. X.R. 

